This invention relates in general to a device for testing the operation of individual components or circuits in a control system. In particular, this invention relates to an improved structure for such a testing device that can be programmed to be functional for only a limited period of time.
Control systems are used to control a variety of structures, vehicles, and machinery, including elevators, automobiles, draw bridges, manufacturing assembly lines, printing presses, steel mills, telephone switch gear, and the like. Control systems can use a variety of mediums for communication between elements within the control system. For example, some control systems use electricity as the communication medium. Other control systems, such as for example pneumatic control systems, use air as the communication medium. Still other control systems, such as for example hydraulic control systems, use hydraulic fluid as the communication medium.
Regardless of the type, control systems typically include a variety of individual control components. The control components are often grouped into control circuits. As one example, electrical control systems include various individual components, such as for example relays, resistors, terminals, contacts, coils, solenoids, sensors, printed circuit boards, and switches.
Malfunctions can occur in control systems. The malfunctions can result from a variety of causes including failure of the individual components or a failure of a group of components. In the event of a malfunction in a control system, service personnel diagnose the problem in order to implement a timely repair. Malfunctions are often diagnosed by analyzing individual components or circuits. One technique for analyzing components or circuits involves temporarily removing the component or circuit from the control system. Another technique for analyzing components or circuits involves temporarily connecting components or circuits to the control system. Temporarily removing or connecting components or circuits to the control system can be accomplished by the use of jumpers.
Jumpers typically include a conduit configured to permit the flow of the communication medium and fasteners positioned at the ends of the conduit. In the example of an electrical jumper, the conduit is a wire configured to permit the flow of electricity as the communication medium between electrical connectors positioned at the ends of the wire. In the example of a pneumatic jumper, the conduit is a hose or pipe configured to permit the flow of air as the communication medium between hose or pipe fittings positioned at the ends of the hose or pipe.
At the completion of the analysis of the malfunction, the jumpers are removed from the control system. In the event the jumpers are not removed after the control system is placed back into regular operation, the jumpers can continue to affect the operation of the control system. It would be advantageous to provide an improved jumper that that can be programmed to be functional for only a limited period of time.